By the experience of active love. Strive to love your neighbour actively and indefatigably. In as far as you advance in love you will grow surer of the reality of God and of the immortality of your soul. If you attain to perfect self-forgetfulness in the love of your neighbour, then you will believe without doubt, and no doubt can possibly enter your soul. This has been tried. This is certain.
...and with a burning pain in my heart I realized how unnecessary, how petty, and how deceptive all that had hindered us from loving was. I understood that when you love you must either, in your reasonings about that love, start from what is highest, from what is more important than happiness or unhappiness, sin or virtue in their accepted meaning, or you must not reason at all.
I love thee so, that, maugre all thy pride,
Nor wit nor reason can my passion hide.
Do not extort thy reasons from this clause,
For that I woo, thou therefore hast no cause
But rather reason thus with reason fetter,
Love sought is good, but given unsought better.
When you get to my age, you’ll measure your success in life by how many of the people you want to have love you actually do love you. That’s the ultimate test of how you’ve lived your life.
I think love is the most unbelievable, and critical, thing in civilization. Everything else is very mechanical and predictable, but love, you can't catch it.