The linguistic philosophy (Oxford School) is a trend in analytical philosophy, critical about the claims of formal logic. Its followers want to investigate problems using an analysis of ordinary language. Peter F. Strawson is one of the most prominent representatives of this line of thoughts. He is also a philosopher who has done a lot toward a rehabilitation of metaphysics in British philosophy. In my paper I present an analysis of Strawson’s metaphilosophical ideas and I offer a critical discussion of Karl R. Popper’s attitude to linguistic philosophy.

Positivism is a family of philosophical views characterized by a highly favorable account of science. The characteristic theses of positivism are that science is the only valid knowledge and that philosophy does not possess a method different from science (scientism). Positivists attempted to eliminate all metaphysical components in the area of philosophy. Wolniewicz was one of the most original Polish analytical philosophers of second part of 20th century and he was a strong opponent of anti-metaphysical tendencies. The author discusses the problem of the relationship between science and philosophy and presents Wolniewicz’s arguments against positivism and scientism.

Gaston Milhaud (1858–1918) was a French modern philosopher, who, having started from mathematics, came to philosophy (especially epistemology) and history of science. His works on the history of science were devoted to Greek science and modern science. Milhaud in his papers claimed that important concepts and principles of science (in different disciplines) result from decisions that simultaneously transcend both experience and logic. He emphasized the role of free creation and activity of the mind. The author discusses central problems of Milhaud’s thought, especially the problem of the relationship between science and philosophy.

Hybrid Renewable Energy Systems connected to the traditional power suppliers are an interesting technological solution in the field of energy engineering and the integration of renewable systems with other energy systems can significantly increase in energy reliability. In this paper, an analysis and optimization of the hybrid energy system, which uses photovoltaic modules and wind turbines components connected to the grid, is presented. The system components are optimized using two objectives criteria: economic and environmental. The optimization has been performed based on the experimental data acquired for the whole year. Results showed the optimal configuration for the hybrid system based on economical objective, that presents the best compromise between the number of components and total efficiency. This achieved the lowest cost of energy but with relatively high CO2 emissions, while environmental objective results with lower CO2 emissions and higher cost of energy and presents the best compromise between the number of components and system net present cost. It has been shown that a hybrid system can be optimized in such a way that CO2 emission is maximally reduced and – separately – in terms of reducing the cost. However, the study shows that these two criteria cannot be optimized at the same time. Reducing the system cost increase CO2 emission and enhancing ecological effect makes the system cost larger. However, depends on strategies, a balance between different optimization criteria can be found. Regardless of the strategy used economic criteria – which also indirect takes environmental aspects as a cost of penalties – should be considered as a major criterion of optimization while the other objectives including environmental objectives are less important.