My Takeaways -
"...if you are looking on anyone as a friend when you do not trust him as you trust yourself, you are making a grave mistake, and have failed to grasp sufficiently the full force of true friendship."
Pretty self explanatory. Seneca also mentions that before we admit someone into our friendship we should judge them, and only when we’ve chosen to admit them as a friend. Do so.
We should be able to tell our friends almost anything. We should be able to trust them.
"Trusting everyone is as much a fault as trusting no one."
While we should strive to trust our friends. We need moderation. Trusting everyone is as bad (and genuinely less safe) than not trusting anyone. Closed off and Open to everyone, neither is good.
"A balanced combination of the two attitudes is what we want; the active man should be able to take things easily, while the man who is inclined towards repose should be capable of action. Ask nature: she will tell you that she made both day and night."
Seneca said this in reference to the previous quote, but it applies to so much more. Balance is necessary, we must trust some and not trust others. We must be able to work hard and still relax when time allows. Or able to laze around/relax and act when needed.
Quote:
“Ask nature: she will tell you that she made both day and night.”