If we are not stupid or insincere when we say that the good or ill of man lies within his own will, and that all beside is nothing to us, why are we still troubled?

Within our control are our own opinions, aspirations, and desires and the demons that distract us from these goals. Outside of our control are such things as what kind of body we have, whether or not we are born into wealth, and how we are regarded by others.

Bid a singer in a chorus, Know Thyself; and will he not turn for the knowledge to the others, his fellows in the chorus, and to his harmony with them?

Consider first the nature of the business in hand; then examine thy own nature, whether thou hast strength to undertake it.

Nothing truly stops you. Nothing truly holds you back. For your own will is always within your control. Sickness may challenge your body. But are you merely your body? Lameness may impede your legs. But you are not merely your legs. Your will is bigger than your legs. Your will needn't be affected by an incident unless you let it.

Cowardice, the dread of what will happen.

You are but an appearance, and not absolutely the thing you appear to be.