self.draw_grid()
            pygame.display.flip()
            while pause:
                for event in pygame.event.get():
                    if event.type == QUIT:
                        running = False
                        pause = False
                    elif event.type == MOUSEBUTTONDOWN:
                        pos = pygame.mouse.get_pos()
                        i = pos[1] // self.cell_size
                        j = pos[0] // self.cell_size
                        if self.life.curr_generation[i][j] == 1:
                            self.life.curr_generation[i][j] = 0
                        else:
                            self.life.curr_generation[i][j] = 1
                        self.draw_grid()
                        pygame.display.flip()
                    elif event.type == KEYDOWN:
                        if event.key == K_SPACE:
                            pause = False
            self.life.step()
            if (not self.life.is_max_generations_exceeded) or (not self.life.is_changing):
                running = False
            clock.tick(self.speed)