Knowing things halfway is a greater success than knowing things completely: it takes things to be simpler than they really are andso makes its opinions more easily understandable and persuasive.
You are your own teacher. Looking for teachers can’t solve your own doubts. Investigate yourself to find the truth - inside, not outside. Knowing yourself is most important.
The instruction of children should aim gradually to combine knowing and doing. Among all sciences mathematics seems to be the only one of a kind to satisfy this aim most completely.
The first man of science was he who looked into a thing, not to learn whether it furnished him with food, or shelter, or weapons, or tools, armaments, or playwiths but who sought to know it for the gratification of knowing.
Let me remind you of the old maxim: people under suspicion are better moving than at rest, since at rest they may be sitting in the balance without knowing it, being weighed together with their sins.