Mebbe beards are to men what underarm hair and leg hair is to wimmins. We are taught in the West during our whole lives to shave that stuph, so when we stop shaving it's like an act of rebellion or liberation, psychologically.
Personally, I like to pull and stroke the beard (sum zipperhead will take this ~OUTT of CONtext and post it along with "$0.10 with news") whilst I am thinking. It seems, psychologically, to make me feel more pensive - I don't know if it actually makes my thinking deeper/better, butt it makes me feel like it does. I find I do this whilst relaxing too - kind of a self-petting of the beard, since I don't have my own bunny fur other than Kai, who will be relocating very shortly.
It might be like pipe smokers. They like to mouth the pipe even when they are nott smoking - it relaxes them and that maybe makes it easier for them to think. I find that minimal anxiety is conducive to thinking - kinda the reverse of test anxiety. I guess I get that fixx with my PLASTIC DISPOSABLE FLEXI-STRAWS for drinking lime-infused iced tea instead of a pipe or a cigar/cigarette/vaper.
I also think better when I doodle. I'm absolutely horrible at drawing - peeps couldn't even recognize my stickmen as stickmen. Butt, I find that doodling letts my mind somehow unwind and relax, and then the thinking seems to just be better. DocCONtango mebbe has a psychobabble 'splanashun for this.
Butt the beard tugging, tweaking has a similar effect. Mebbe it is an ~OUTTlet for the 'nervous energy' in DaBrain, so then we can better focus/CONcentrate with that nervous energy abated in doodling, beard tugging, pipe mouthing, cigar chomping, etc.
I know several high-level mathematicians who have tole me over the decades that they cannot think deeply about their math prollems until they burn a cigarette. Mebbe that's the nicotine or maybe it's the habit of giving your hands something to do so they are nott restless and unoccupied. Some of the last bastions of smokers in academia are in maths departments. And a lott of the smokers are young too, so it's nott just a holdover from the old mathetistas. There seems to be a definite correlation across the age spectrum between tobacco smoking and math prowess/ability.
Fortunately, DaSun does nott smoke and his maths are strong. Butt he is nott a 'mathematician' as his sole formal area of work - he just uses a lott of high-falutin' maths. The career professional mathematicians are a whole different breed of cat.
Sumday we may have pharmaceuticals or devices that we can take/use to think better - and nott caffeine, Adderall, Ritalin, cocaine, and benzedrine/dexedrine/methamphetamine. Butt drugs or devices that will allow intense concentration or brain storming creativity and the like. We might be able to tune our brains for specific tasks.
Butt then again, I doubt that human civilization will last that long. My over/under for modern civilization is about 100 to 150 years.