"The great question which, in all ages, has disturbed mankind, and brought on them the greatest part of their mischiefs . . . has been, not whether be power in the world, nor whence it came, but who should have it."
Locke addresses the issue of power. He argues that power exists and will be distributed among people regardless of the situation. The great question is who should be given power. According to Locke, this distribution of power is the source of most of mankind's suffering. This is true either because unjust men are given power or because others are desperate to have it which never will.
"One unerring mark of the love of truth is not entertaining any proposition with greater assurance than the proofs it is built upon will warrant."
Locke believes that one who actually is committed to truth will believe arguments more readily than their supporting evidence deserves. Another way to say this is the lover of truth is eager to believe what he hears. Thus he is likely to believe something, even if the evidence is not indisputable.
"It is therefore worthwhile, to search out the bounds between opinion and knowledge; and examine by what measures, in things, whereof we have no certain knowledge, we ought to regulate our assent, and moderate our persuasions."
Most people believe what they believe simply because they've heard that idea before. In this quotation, Locke urges his readers to consider why they have adopted the ideas they have. Knowledge should be criticized using discernment so that each opinion is recognized as theory and each piece of knowledge as fact.
"Personal Identity depends on Consciousness not on Substance."
Locke seems to believe that the individual determines their identity. What sort of person they are or any outside circumstances are not a part of their identity. He says that identity is composed of what that individual thinks of himself or herself. That is what they'll become.
