PERHAPS no man in public life knows Ronald Reagan and what makes him tick better than John P. Sears III, the astute political operative who did so much to put Reagan into the presidency.
Over several years Sears spent hundreds of hours in conversation with Mr. Reagan before being ousted from his role as campaign manager in 1980. He is widely regarded as a friendly but objective critic of the President.
Here's how Mr. Sears appraised Ronald Reagan in a recent interview:
Q: There's much talk these days about Reagan's ability to ''walk away'' from what many see as his blunders, and, particularly, his apparent serenity in the face of reverses. Is that a public pose? Is he sometimes privately devastated at such moments?
A: Never. That's Reagan being Reagan. What you see is what you get.
Q: But how can he do this? Doesn't he recognize the difficulty he is in at such times?
A: Well, it seems that he isn't in any difficulty because he is able to walk away, as you say. He's a fellow who has a lot of moves that really account for this. You know, you hear talk about this being luck or something. It isn't luck. It really comes from a long time back - before he was in politics - and having instincts about image that were necessary in his acting career.
The temptation that so many people have is to try to chase him on his so-called blunders or on his positions where he apparently is taking a minority position. People have been trying that for 18 years, since he's been in politics. It's always unrewarding. You can chase Reagan down a road. But when you get very close to him he turns around and hugs you to death. Or he just winds up behind you somewhere.
Q: So these are ''moves'' by Reagan, part of his political and, earlier, acting instinct and not the ''Reagan luck'' so many people are talking about today?
A: No, it isn't luck. I'll tell you what it is in part, too: With most politicians when they sense they have made a mistake or they have been told in the press that they have made a mistake, it is their natural inclination to try to justify what they did.
Reagan never tries to do that. He may not admit he was wrong. But when people are criticizing him for having troops in Lebanon he may get up and say that he is going to be more loyal to American interests than Tip O'Neill - but the next week he's got the troops out, or on their way out.
Q: How do you explain his outward serenity? Doesn't he ever get ''down,'' privately in the face of reverses?