The only limits we have are the limits we give ourselves.
A rower knows the underlying presence that moves a boat; it is quite simply force and energy. The force needs to be penetrating, and the energy needs to be driving and uninhibited.
While power is important, efficiency is critical. Many have worked hard and gone slow.
Through the discovery of Buchner, Biology was relieved of another fragment of mysticism. The splitting up of sugar into CO2 and alcohol is no more the effect of a 'vital principle' than the splitting up of cane sugar by invertase. The history of this problem is instructive, as it warns us against considering problems as beyond our reach because they have not yet found their solution.
Our legacy is really the lives we touch, the inspiration we give, altering someone's plan - if even for a moment - and getting them to think, cry, laugh, argue. More than anything, we are remembered for our smiles; the ones we share with our closest and dearest, and the ones we bestow on a total stranger, who needed it RIGHT THEN, and God put you there to deliver.
There will be certain points of time when everything collides together and reaches critical mass around a new concept or a new thing that ends up being hugely relevant to a high percentage of people or businesses. But it's really really hard to predict those. I don't believe anyone can.
A life without impact and contribution is a very empty life, so use your life to make the world better.