Science of Shaving

It’s time to study behavior again. But this time, it’s time to stop being so serious. I know I bore most of you, if not all of you, because no one really reads these entries. Who wants to know more about love, hate, or the economy? No one, actually. No, interest lies in what is truly the most important to our selfish selves, maximizing personal pleasure and minimizing pain.

One source of pain is making ourselves look as attractive as possible – it takes work! And money. Lots and lots of money. The beauty industry is billions and billions of dollars large. In fact, if you take a look at the global economy, last estimated to be around 40t USD, I’m willing to bet about a trillion is devoted to beauty in one of its many forms. [1]

One of the many things men and women do to appear more beautiful is remove hair – shaving. Now, why is hair removal considered beautiful? That’s a subject for another day, but one that resides smack dab inside the study of behavior. For now, my fun-loving science oriented reader, let’s take it as axiomatic that hair removal (sans tête) is beautifying.

And painful. You have to take the time to prepare the bath, or shower, or sink. You have to buy equipment, then scrape that blade across your naked flesh. Time, money, energy, all add up to pain.

Adding insult to injury, that equipment you’re using? It’s not getting any younger. Every time you scrape that thin edge of stainless steel across your tender flesh, you’re tearing a few atoms away from the exposed fragile peaks comprising its surface.

What? Did you think that steel was flat and featureless? Hah! Shrink yourself so that you harbor an atom’s eye, and you’ll see what our best technology is capable of. A chunk of steel, yes, but with two sides coming together at a five degree angle or so. The actual edge looks like the trunk of a tree, and nowhere we look can anything be called smooth.

Relative to one of our hairs, this crudely shaped barbaric axe is sufficient, because your atomic eye sees even the finest hair as a huge, roundish stalk of asparagus. Its top reaches beyond our sight, and our axe is hard compared to the soft protein forest. This is why we are able to tear and cut the hair tree forest down.

In the process, some of our less well attached, more exposed pieces of atomic steel have also been removed, or shuffled around. We call this wear and tear. Our blade is becoming blunt.

Which brings us back to behavioral science, and how it relates to something as mundane as shaving. Shaving is a behavior, although a miniscule behavior in light of us trying to understand the big picture. Yet, shaving is something we do often, regularly, and think about too much. How then can behavioral science help us shave?

First, we have to understand the physics and chemistry. Don’t worry, we don’t have to understand too much. We talked about how the blade cuts the hair already. That’s the physics. Another wear factor is how the blade glides across your face or legs. Reducing those cutting and gliding forces reduces the force necessary to cut the hair – resulting in a closer shave and longer lived blades. There’s your chemistry.

For this to happen, you need two fundamental components – a hydrating / lubricating substance, and time. Time is a huge factor because simply adding water to hair helps soften them, but it takes about a minute for hair to be fully wetted.

Then there’s the substance. Many of us use special preparations and buy billions and dollars of various products, and have developed our own rituals. But what’s needed is a substance that is both highly lubricating and an effective hair moisturizer.

Here’s where the science comes in; how do you know you’ve improved and maximized your shaving style? The method or test that I’ve been following for the past year uses this simple metric – how long does my blade last before it needs to be changed? In the interest of science I’ve decided to publish my raw data here [2].

How do I know when my blade needs changing? Good question, a great question. I used to change out my two-bladed cheap razor once a week, without fail, on Sunday morning. So, every Sunday, I’d have a brand new blade so that I’d get the most perfect shave to be able to impress my wife.

Well, I started a new system. Not just a new soap (which rocks by the way [3]) but a new method of preparation. What’s my method? Again, in the interest of science, I’ll share these personal shaving behaviors with you.

First, start with wetting the face. Then, with a drop of my super-soap, I’ll wash my face. Wash the soap off my face, then squirt a full squirt [4] into my hands. I spread the soap on my hands a few times to lather it up, then apply it to the shavable part of my face. Then I look at myself a second to make sure I’ve got everything covered, then get the razor from the cupboard. I know, I should have done that at the very beginning, but I always forget.

Wait, I almost forgot another step. Right after I’ve lathered up, I rub off the excess soap on my hands onto the sink. Our sink seems to accumulate this hard and rough surface scale from toothpaste and makeup. I don’t know how it gets there, but normally my wife spends weekends scrubbing the sink so that it’s nice and shiny and smooth. Guess what? By rubbing my soap on the sink, it cleans it up just as if she scrubbed it. Yes, I know this isn’t directly relevant to shaving, but it’s what I do, and in the interest of full disclosure, well, there you have it.

So, getting back to the shaving thing. I rinse my hands one more time, pick up the blade, and start cutting away. No difference there, just start scraping, washing the blade off, and scraping some more. A closeup look to make sure I didn’t miss something major, and I’m done.

Overall, it takes me about as long to shave using this new method as it did with canned shaving cream, gel cream in tubes, and even fancy soap disks in a shaving mug complete with beaver hair brushes. There’s one big difference.

My blades. My blades last almost four weeks now! Truly. The blade I used this morning was new as of August 22, 2013. That’s almost a month ago, and that’s for a two bladed razor. I don’t know about you, but every time I’m asked to pay $50 for a few razor heads it makes me gasp. So knowing that a set of twelve is going to last me a year is a great solace to my wallet.

Time for a confession. I read one of those glossy superficial articles on-line a few days ago. [6]  The expert was someone who’d started a store in Manhattan selling $50 soaps for closer shaves. He sold the store to Proctor and Gamble, and he’s been kept on as the figurehead entrepreneur and spokesman. His secret to everyone was the exact same advice as what I’ve described above, time and lubrication. Here’s the difference. His purpose is getting publicity is to drive people to his store, where they can buy a solution without having to think about it in any way. Why think? It’s hard work. It’s so much easier to simply trust this nice guy in the article, give him $50, and shave away. [5]

The reason we have to think is exactly because of that assumption; we can’t trust a corporation trying to make money off of us. We have to be skeptical, that’s the backbone of science. That’s why we have to measure our success, and our failures. And we have to share them with each other. Replication and validation are the two pillars that hold up all of our scientific knowledge today.

So please, analyze yourself! That’s the behavioral science part of this exercise. You’ll be surprised how many of our own behaviors can be subject to analysis, just like shaving. Something we have been taking for granted all these years can be approached in new ways. Who knows? You might stumble onto something even greater! Feel free to add your ideas below.

Thanks for reading. Pardon me now – I have to go shave.

[1] And I’m talking many many forms of beauty. Not just cosmetics, eye shadow, blush, and lipstick. It includes underarm deodorant, fancy shampoos, teeth whitening, cosmetic surgery, hair coloring, nail cleaning, wigs, haircuts, and a lot of things we simply take for granted. All of these behaviors, however, have one fundamental purpose in mind; they are ways to make us more beautiful.

[2] Here’s my raw data in spreadsheet form, to date:

Soap type

Blade type

Start date

End date

total days

UE-brand Bar

G-brand 2 blades

Jun 3, 12

Jun 18, 12


UE-brand Bar

G-brand 2 blades

Nov 13, 12

Nov 24, 12


UE-brand Bar

G-brand 2 blades

Nov 27, 12

Dec 8, 12


UE-brand Bar

G-brand 2 blades

Dec 9, 12

Dec 30, 12


UE-brand Bar

G-brand 5 blades

Jun 19, 12

Sep 2, 12


UE-brand Bar

G-brand 5 blades

Jan 3, 13

May 13, 13


UE-brand Bar

G-brand 2 blades

Dec 31, 12

Feb 6, 13


UE-brand Bar

G-brand 2 blades

Feb 7, 13

Mar 16, 13


UE-brand Bar

G-brand 2 blades

Mar 17, 13

May 7, 13


UE-brand Bar

G-brand 2 blades

May 8, 13

May 26, 13


UE-brand Bar

G-brand 2 blades

May 27, 13

Jul 13, 13


UE-brand Liquid

G-brand 2 blades

August 22, 13

still going strong!


G-brand Cream

G-brand 5 blades

Sep 3, 12

Oct 4, 12


G-brand Cream

G-brand 5 blades

Oct 5, 12

Nov 1, 12


[3] Really, my soap rocks. It started out as being a strong natural soap for men in factories, but after three months their WIVES asked them to bring it home. Why? Because the women noticed how soft and healed their men’s damaged skin had become. It seems that this is the most powerful natural soap on the market. Read more about this soap at

[4] For the bottle I use, a squirt is about 1.3 milliliters.

[5] More true confessions here. Our company makes this super-soap. That’s one of the reasons why I’ve gotten so technical about shaving. But that’s the whole purpose of this article. You don’t have to ‘trust’ me like the guy who started those P&G stores. Does our soap outperform yours? Test my statement yourself. Replicate! Validate!

[6] Finally found the article, a few days after writing this entry, at …