The first type of an intellectual effort let us call it a logical one. The idea is that by presumption of all possible actions of the opponent and by the estimation of all positions the player chooses the way to continue the game which can lead him to victory.
Chess players have a "tree" choice of options to choose from. The player advisors all possible variants in turns and all possible answers as well. Then all his her answers and so on. While analyzing the game this way, ideally the player chooses the variant which could lead him to victory faster (the mate to the adverse king or to the damping material advantage).
The similar "tree" of choices we can also find in poker. But here the poker player analyzes possible moves of the opponent, the game reaction to any action of the player and all these actions are done with a glance of possible changes of game situation as a result of emergence of next cards.
The "tree" of choices in chess is incomparably stronger and consist of far more branches than in poker. Our conclusion is that a logical intellectual effort is present in both, chess and poker, however, the role and sense of it in chess are more important.
The above-mentioned type of an intellectual effort is rarely used in practice. The majority of game situations are uncertain and we can seldom find a chance to find the updated version which can lead us straight to victory. And of course, this type of search for decision is more feasible to machines not for a human being. Thereafter we proceed to description of the second type of an intellectual effort. Let's call it analytic. The main sense of it is that the player accounts those variants that can lead him to one or another position. The position which the player wants to achieve so badly does not guarantee him victory. But the player believes if the desirable position is achieved he has the evident position advantage. This means that the player estimates his total position benefit status rather highly and expects to find moves to continue the game in such a way that is more likely to lead him to victory. The desirable position will be very comfortable for a further game of the player or very uncomfortable for a further game of his opponent. Thus, by having achieved the objectively equal position, only because of its unique features the player expects his chances to be higher than those of his opponent.
In chess in the majority of cases you do not have a possibility to spend some time counting an updated version that can lead to victory, the player tries to get a position that can help him to hold a position advantage or a position that can help him to get better oriented. The factors of open lines, active disposition of figures, territorial advantage and so on refer to the position advantage in chess. In addition every player has his her preferred structure, the ways of attack continuation or arrangement of defense and so on. Thus, under the other equal conditions he will seek a chance to achieve only these kinds of positions.